The present invention relates to a packaging container of aerosol type, comprising an outer casing, which is generally cylindrical, suitable for containing a compressed gas, in particular compressed air, and a liquid intended to be expelled in the form of a spray or a foam through a dispensing nozzle by actuation of a dispensing valve mounted at the upper part of the casing and possibly connected to an immersed tube.
More precisely, the invention relates to such a packaging container, of the type which can be recharged with compressed gas, and comprising for this purpose, preferably in its end wall, a filling adaptor passing through the wall of the casing in a leaktight manner and provided at its outer end with means for connection to a compressed gas source, such as a compressor, and, at its inner end, with an orifice opening inside the container.
In order to make the container leaktight, provision has been made to fit an elastic diaphragm provided with peripheral holes onto the inner end of the adaptor. When compressed gas is admitted, the diaphragm lifts away from the end of the adaptor, in line with the orifice made therein, and the compressed gas enters the container through peripheral holes in the diaphragm.
When the compressed gas supply is stopped, the diaphragm is again applied onto the end of the adaptor, covering the orifice made therein.
In such an embodiment, the compressed gas is introduced into the container in the lower part of the latter containing the liquid, which leads to the formation of bubbles in the liquid and thus to the formation of a foam in the container.
Furthermore, the diaphragm made at the end of the adaptor is in contact with the liquid and is thus exposed to chemical attack which can have an effect on its qualities and therefore lead to sealing defect problems through the adaptor.
Another embodiment, known by FR-A-2,380,075, consists in making the adaptor in the form of a filling valve provided with spring non-return means and connected to a filling tube whose free end opens inside the casing of the container above the level of the liquid contained in the latter.
This solution makes it more complicated to produce the adaptor and to mount it on the casing, but without avoiding the sealing defect problems mentioned previously.